The Period

The period is used to end all sentences except those that are direct questions or exclamations. Periods are also used in abbreviations.

1. Use a period to end a declarative or imperative sentence.

A declarative sentence makes a statement.

All is fair in love and war.

An imperative sentence issues a request or command.

Please do not leave until you have said good-bye.

Do not use a period if the sentence is a genuine exclamation. Use an exclamation point.

That speech was fantastic!

Do not use a period with a sentence that asks a direct question. Use a question mark.

Will the picnic be canceled?

However, do use a period if the sentence is a statement reporting a question indirectly.

Sara asked if the picnic would be canceled.

2. Use a period in certain abbreviations.

The following are examples of some abbreviations which use periods:

Mr.

B.A.

e.g.

A.M. or a.m.

ft.

Mrs.

M.A.

i.e.

P.M. or p.m.

oz.

Ms.

Ph.D.

etc.

Capt.

dept.

Dr.

R.N.

Ave.

c.o.d.

P.O.

Do not use a period with U.S. Postal Service abbreviations for states.

Long Beach, CA Longview, TX Detroit, MI

Do not use a period with most abbreviated names of organizations or with commonly used abbreviations that replace words.

NATO

IRS

CSU

NBA

NAACP

TV

VCR

CD-ROM

However, sometimes usage varies, such as in the abbreviation USA or U.S.A., both of which are acceptable. When in doubt, consult a dictionary or style manual, or a publication by the agency or group in question.

If a sentence ends with a period marking an abbreviation, do not add a second period.

You will need to bring your own towels, sheets, blankets, pillows, etc.